In a receiving apparatus such as a copier, a laser printer, a complex machine or the like, an endless belt has been used in a photosensitive devices, an intermediate transfer devices, a transfer carrying devices, a transferring separation devices or the like, which is mounted in an electrophotographic image forming apparatus. FIG. 1 shows an endless belt used in an image forming apparatus using an intermediate transfer belt. Referring to FIG. 1, when a carrier transport layer (CTL), which is located on the surface of an organic photoconductor drum (OPC drum, hereinafter referred to as a ‘drum’) 4, is charged with electricity {circle around (1)}, and the electrically charged drum 4 is exposured with a laser beam {circle around (2)}, electric charges move to the surface of the drum 4, so that the surface of the drum is made relatively positive (+), thereby forming a latent image. While a developing roller (magnetic roller) 3 rotates with the drum 4 at a minute distance, relatively negative (−) toner particles adhere to the surface of the drum exposured with the laser beam to form a letter or picture. The negative (−) toner particles adhering to the surface of the drum are transferred to the back of paper in a state of positive (+) electric charge by a transfer roller 5, thus forming an actual image. The toner formed on the paper is thermally pressed by a fuser roller 6 to be completely fusion-bonded on the paper, and then outputted. Then, the OPC drum 4 is physically or electrically cleaned using a cleaning blade 7 to form a new image on the drum 4. Further, electric charges remaining on the surface of the drum 4 are neutralized by a predetermined amount of light by erasing {circle around (8)} to put the drum 4 back in an initial state, and then the drum is charged with electricity again.
In order to precisely rotate and drive an intermediate transfer belt, the intermediate transfer belt is required to have high linearity because a plurality of rollers coming into contact with the intermediate transfer belt must be parallel with a shaft. Further, the intermediate transfer belt is required to have uniform thickness and length. When the requirements are not satisfied, the intermediate transfer belt becomes meanderingly warped, so that exposure position or transfer position is missed, with the result that an image is blotted or distorted, and thus the intermediate transfer belt meanders to be damaged.
In order to prevent the meandering of an endless belt, there has been reported an endless belt which is provided at both ends thereof with a meandering prevention guide made of an elastic body such as rubber or urethane. This endless belt provided with the meandering prevention guide is usefully used in various electrophotographic image forming apparatuses because it performs its functions in a very stable manner and is cheap.
As examples of conventional technologies related to such a meandering prevention method, Japanese Unexamined Patent Application Publication No. 07-187435 discloses a method of providing a meandering prevention guide to an endless belt using an acrylic additive. However, when the acrylic additive is used, the acrylic additive can be detached from the meandering prevention guide, the meandering prevention guide must be supported until the acrylic additive is cured, and it is difficult to have highly-precise linearity. Further, when the endless belt is continuously driven while the meandering prevention guide is attached to the endless belt using the acrylic additive, the meandering prevention guide may be detached from the endless belt when the endless belt is driven along the curve of a roller for a long period of time.
Further, Japanese Unexamined Patent Application Publication No. 2000-310291 discloses a method of providing a meandering prevention guide to an endless belt using an acrylic or silicon-based additive containing a crosslinking agent or an initiator, wherein the meandering prevention guide is provided to the endless belt by irradiating the additive with ultraviolet or drying the additive at high temperature. However, this method is complicated. Further, this method is problematic in that the meandering prevention guide, which is an elastic body, is thermally deformed during the high-temperature drying, and thus its shape cannot be maintained constant.
As an alternative to the above methods, there is a method of attaching a meandering prevention guide to an endless belt using double-sided adhesive tape made of an acrylic additive. However, this method is also problematic in that, although the initial adhesivity of the double-sided adhesive tape is good, the adhesive strength between the belt body and the meandering prevention guide is insufficient, and the durability of the belt is low.
Meanwhile, Japanese Unexamined Patent Application Publication No. 2000-122439 discloses a method of attaching a meandering prevention guide to a belt using a one-component modified epoxy resin (liquid additive) that is cured at room temperature. However, there is a problem in that the liquid additive protrudes, and the initial adhesivity thereof becomes low.
In order to solve the above problem, Japanese Unexamined Patent Application Publication No. 2001-206522 discloses a method of attaching a meandering prevention guide to a belt using an adhesive layer formed of an adhesive composition including an acrylic copolymer and a crosslinking agent. This method was proposed to solve the problem that an endless belt and a meandering prevention guide are weak to shear loading. However, this method is also problematic in that the peel strength of the adhesive layer between the endless belt and the meandering prevention guide at an angle of 180° is at most 7N/20 mm, and thus the adhesive layer cannot have sufficient adhesivity.